and there's an error
Mar 20 17:08:58 localhost postfix/lmtp[28338]: 3F33548D4: to=, relay=none, delay=1, status=bounced (Host o
r domain name not found. Name service error for name=wwzimbra.com type=A: Host found but no data record of requested type)

(1) Why lmtp looking for wwzimbra.com A record of the domain itself?

When I add A record as
@ IN SOA localhost. root.localhost. (
IN NS localhost.
A 10.1.254.10
MX 10 mail.wwzimbra.com.
mail A 10.1.254.40